An international investigation into the assassination of a senior Palestinian militant in the Persian Gulf region has taken British police to Israel.

A special British police investigator has arrived in Israel to probe the use of false British passports in the assassination of a senior Hamas operative in Dubai last month. The investigator will meet with dual Israeli-British citizens whose passports were used by the alleged hit team and who claim they were victims of identity theft.

Dubai police blame Israel's Mossad spy agency for the killing of Hamas arms dealer Mahmoud al-Mabhouh in his hotel room. Using closed circuit video, police have identified a 26-member hit team which entered Dubai on false passports. At least 16 of those identified bear the names of Israelis who immigrated to Israel from abroad and hold foreign passports, including six from Britain.

Britain, Ireland, France and Australia have protested to Israel over the alleged use of fake passports belonging to their citizens. But Israel, which refuses to comment on Mossad operations, has remained silent.

Former Israeli diplomat Avi Pazner said, "Nobody can accuse Israel of any wrongdoing because we don't know if the Mossad did it or didn't do it."

Despite the diplomatic fallout abroad, the story is getting positive reviews at home in Israel and job applications to the Mossad have surged. Pazner says it is all about intrigue. "It's a very sexy story, of course; you know all those cloak-and-dagger stories are extremely sexy," he said.

Israel is celebrating the biblical holiday of Purim, when it is customary to dress up in costumes. And the most popular costume this year is that of a Mossad spy.